At least 40 people were killed and 90 wounded, most of them soldiers, when three car bombs struck the heart of Syria's second city Aleppo today, a monitoring group said.

At least 40 people were killed and 90 wounded, most of them soldiers, when three car bombs struck the heart of Syria's second city Aleppo on Wednesday, a monitoring group said.

"A medical source said that at least 40 people were killed and 90 injured," said the Syrian Observatory for Human Rights. "Most of them were regime troops."

Meanwhile, official television channel Al-Ikhbariya said 31 people were killed and dozens wounded.

"The toll could rise because many people were badly injured," a city official told AFP, shortly after three bombs exploded around Saadallah al-Jabiri Square, near a military officers' club and a hotel.

Two of the blasts hit the area near the club within a minute of each other.

A third car bomb then exploded some 150 metres (yards) away in the Bab Jnein district, at the entrance of the Old City neighbourhood of Aleppo.

Near the officers' club, part of the facade of a hotel was destroyed by the force of the blasts, an AFP correspondent at the scene said, adding that a two-storey cafe collapsed completely.

The face of one of the injured people was covered in blood, the correspondent said.

"We heard two enormous explosions, as though the gates of hell were opening," Hassan, a 30-year-old man who works in a nearby hotel, told AFP.

"I saw thick smoke, and I helped a woman on the pavement whose arms and legs were completely dislocated," said Hassan.

A shopowner whose store is located a block away from the officers' club said: "I pulled out from the rubble a child less than 10 years old who has lost a leg."

All government buildings in the area were closed, he added.

Official television channel Al-Ikhbariya showed massive destruction in the square.

At least two buildings collapsed completely, and bloody corpses were laid out on the rubble, the broadcaster showed.

"There are still people trapped under the rubble!" called out men in the square, as the channel showed people evacuating some of the victims.